Geocell-Based Drainage Base for Synthetic Turf

ABSTRACT

A drainage base system for a synthetic turf includes a geotextile liner disposed above a prepared subgrade, a first geocell layer having a plurality of interconnected open geometrically-shaped cells installed above the geotextile liner, the plurality of open geometrically-shaped cells being filled with a drainage aggregate, a shock absorbing layer disposed above the first geocell layer, and an artificial turf layer installed above the shock absorbing layer.

RELATED APPLICATION

This application claims the benefit of U.S. Provisional Patent Application No. 63/039,358 filed on Jun. 15, 2020, incorporated herein by reference in its entirety.

FIELD

The present disclosure relates to a geocell-based drainage base for a synthetic turf.

BACKGROUND

A geocell layer (also known as a cellular confinement system or CCS) is a layer of material composed of a matrix of interconnected open honeycomb-shaped (or other geometric shaped) cells has been used to provide a stable base for pavement, roadway, and retaining walls, as well as for soil erosion prevention and lining the sloped embankment of a channel. One example of geocell product is one manufactured by Industrial Fabrics, Inc. under the trademark BASELOK™.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a pictorial representation of a first embodiment of a geocell-based drainage base for a synthetic turf according to the teachings of the present disclosure;

FIGS. 2-5 are simplified cross-sectional diagrams of various embodiments of a geocell-based drainage base for a synthetic turf according to the teachings of the present disclosure; and

FIGS. 6 and 7 are simplified cross-sectional diagrams of various embodiments of a geocell-based drainage base incorporating directed drainage for a synthetic turf according to the teachings of the present disclosure.

DETAILED DESCRIPTION

FIG. 1 is a pictorial representation of a first embodiment of a geocell-based drainage base 10 for an artificial or synthetic turf surface according to the teachings of the present disclosure. The basic design of the invention includes an impervious liner or a layer of geotextile fabric 12 installed on top of a prepared subgrade 14, on top of which is installed one or more layers of geocell 16 with open cells that are filled with a free-draining aggregate. The free-draining aggregate may include sand, gravel, or any suitable porous media. On top of the geocell layer 16 is a natural turf or artificial turf 18 with infill. It should be noted that the prepared subgrade 14 may or may not be compacted. FIG. 2 shows a simplified cross-sectional diagram of the first embodiment of the geocell-based drainage base for a synthetic turf.

FIGS. 3-6 are simplified cross-sectional diagrams showing various embodiments of a geocell-based drainage base for a synthetic turf according to the teachings of the present disclosure. The geocell-based drainage base embodiment 30 shown in FIG. 3 includes an impervious liner or a layer of geotextile fabric 32 installed on top of a prepared subgrade 14, on top of which is installed a layer of geocell 34 filled with free-draining aggregate (e.g., gravel). Laid over the top of the geocell layer 34 is one or more shock absorbing layers 36 fabricated from a rubber material or other suitable materials. Installed on top of the shock absorbing layer 36 is a natural turf or artificial turf with infill 38.

The geocell-based drainage base embodiment 40 shown in FIG. 4 includes an optional liner or a layer of geotextile fabric 42 installed on top of a compacted or prepared subgrade 14, on top of which is installed a layer of geocell filled with native soil 44. On top of the geocell layer a liner or a layer of geotextile fabric 46 and a second layer of geocell 48 filled with free-draining aggregate may be installed. Installed on top of the second geocell layer 48 is a natural turf or artificial turf with infill 49.

FIG. 5 shows another geocell-based drainage base embodiment 50, which includes an optional liner or a layer of geotextile fabric 52 installed on top of a prepared subgrade 14, on top of which is installed a layer of geocell filled with native soil 54. On top of the geocell layer 54 a liner or a layer of geotextile fabric 56 and a second layer of geocell 57 filled with free-draining aggregate may be installed. Installed on top of the second geocell layer 57 is a shock absorbing layer 58. A natural turf or artificial turf with infill 59 is then installed as the topmost layer.

In yet another geocell-based drainage base embodiment 60 shown in FIG. 6, an impervious liner or a layer of geotextile fabric 62 is installed on top of a prepared subgrade 14, on top of which is installed one or more layers of geocell filled with native soil 64. The geocell layer 64 further incorporates one or more drainage pipes 66 designed to direct and conduct water drainage. On top of the geocell layer 64 is a natural turf or artificial turf with infill 68. The drainage pipes 66 may incorporate segments that are perforated and non-perforated and are arranged in a pattern that is configured to efficiently guide and conduct water out of the region of interest, such as a sports field.

FIG. 7 is an illustration of another embodiment 70 in which directed drainage is incorporated in one or more geocell layers. In this embodiment of the drainage base, an impervious liner or a layer of geotextile fabric 72 installed on top of a prepared subgrade 14, on top of which is installed one or more layers of geocell 76 filled with free-draining aggregate, which may sandwich a liner/geotextile layer. The open cells of the geocell layer 76 are filled with the aggregate. A plurality of cell plugs 78 are inserted in selected open cells in the geocell layer(s) 76 either randomly or in a predetermined pattern, such as forming a linear drainage path. These plugs 78 are used to temporarily block selected cells in the geocell layer during installation. The open cells that are not occupied by the cell plugs are then filled with native soil. Then the cell plugs 78 can be removed from the geocell layer(s) to allow those open cells to be filled with a more porous media or aggregate to achieve drainage objectives. In this manner, water may flow through this selectively more porous geocell layer 76 into another geocell layer filled with free-graining aggregate or trench drain located directly below it. The cell plugs 78 may be fabricated from any suitable material that can withstand the actions of native soil being dropped and moved around into the neighboring open cells in the geocell layer 76. Multiple cell plugs 78 can be connected in some way to enable easy insertion and extraction. On top of the geocell layer 76 is a natural turf or artificial turf with infill (not explicitly shown in this figure).

In an alternate embodiment, all or a selected subset of cells may be filled with a native soil may be filled to, for example, 30% of each cell to stabilize the subgrade, and then a mixture of free draining stone and shock absorbing material may to be added to these same cells the rest of the volume to meet the draining and shock absorbency requirements. In this embodiment, layers of different kinds of media can be used in all or some of the cells to achieve the drainage, shock attenuation, and stabilization objectives, and the cell plugs can be used to strategically fill selected open cells in the geocell.

The geocell layer is a structural layer fabricated from a polyethylene material that incorporates arrays of interconnected open cells of a particular geometric shape (e.g., square, triangle, hexagon, etc.) that have tensile and compression strength when filled with some type of aggregate such as native soil or gravel. The infill material for the geocell layer may be cohesionless soil, sand, gravel, or any other type of aggregate that allows free-drainage. Other suitable types of fill are contemplated such as synthetic polymer particulates. The geocell layer may be fabricated in any suitable thickness for the particular application and installed in panels or strips. The infill particulate for the artificial/synthetic turf may comprise any type of elastomeric material such as styrene-butadiene rubber, butyl rubber, cis-polyisoprene rubber, neoprene rubber, nitrile rubber, ethylene propylene diene monomer, polyurethane, elastomeric polyester and other similar materials. The proposed structure provides a stable drainage base for a region of interest such as a sports field that allows rainwater to easily drain and be conducted away from the area. It should be noted that although the focus herein has been on a drainage base for a sports field, this system can be used as a substrate for many other applications, such as parks, recreational areas, and parking lots.

The features of the present invention which are believed to be novel are set forth below with particularity in the appended claims. However, modifications, variations, and changes to the exemplary embodiments described above will be apparent to those skilled in the art, and the geocell-based drainage base for a synthetic turf described herein thus encompasses such modifications, variations, and changes and are not limited to the specific embodiments described herein. 

What is claimed is:
 1. A drainage base system for a synthetic turf comprising: a first geocell layer having a plurality of interconnected open geometrically-shaped cells installed above a subgrade, the open geometrically-shaped cells being filled with a first aggregate; and an artificial turf layer installed above the first geocell layer.
 2. The drainage base system of claim 1, further comprising a geotextile liner disposed between the subgrade and first geocell layer.
 3. The drainage base system of claim 1, further comprising a shock absorbing layer disposed between the first geocell layer and the artificial turf layer.
 4. The drainage base system of claim 1, further comprising a geotextile layer and a second geocell layer with a second plurality of open geometrically-shaped cells filled with a second aggregate disposed between the first geocell layer and the subgrade.
 5. The drainage base system of claim 1, wherein the plurality of open geometrically-shaped cells of the first geocell layer incorporates a drainage pipe.
 6. The drainage base system of claim 1, wherein a first selected ones of the plurality of open geometrically-shaped cells of at least one of the first and second geocell layers are filled with a first type of aggregate, and a second selected ones of the plurality of open geometrically-shaped cells of at least one of the first and second geocell layers are filled with a second type of aggregate.
 7. A method of installing a drainage base for a synthetic turf, comprising: installing a first geocell layer having a plurality of interconnected open geometrically-shaped cells above a subgrade; filling the plurality of open geometrically-shaped cells with an aggregate with excellent drainage properties; and installing an artificial turf layer above the first geocell layer.
 8. The method of claim 7, further comprising installing a geotextile liner between the subgrade and the first geocell layer.
 9. The method of claim 7, further comprising installing a shock absorbing layer between the first geocell layer and the artificial turf layer.
 10. The method of claim 7, further comprising installing a geotextile layer and a second geocell layer having a plurality of interconnected open geometrically-shaped cells filled with native soil between the first geocell layer and the subgrade.
 11. The method of claim 7, wherein installing the first geocell layer comprises installing a drainage pipe.
 12. The method of claim 7, further comprising: blocking selected ones of the plurality of the open geometrically-shaped cells in the geocell layer; filling remaining unblocked open geometrically-shaped cells in the geocell layer with a first type of aggregate; unblocking the selected ones of the plurality of the open geometrically-shaped cells in the geocell layer; and filling the now unblocked open geometrically-shaped cells in the geocell layer with a second type of aggregate;
 13. The method of claim 12, wherein blocking selected ones of the plurality of open geometrically-shaped cells in the geocell layer comprises inserting a plurality of cell plugs in the selected cells.
 14. A drainage base system comprising: a geotextile liner disposed above a prepared subgrade; a first geocell layer having a plurality of interconnected open geometrically-shaped cells installed above the geotextile liner, the plurality of open geometrically-shaped cells being filled with a drainage aggregate; a shock absorbing layer disposed above the first geocell layer; and an artificial turf layer installed above the shock absorbing layer.
 15. The drainage base system of claim 14, further comprising a second geocell layer having a plurality of interconnected open geometrically-shaped cells filled with native soil disposed between the first geocell layer and the geotextile liner.
 16. The drainage base system of claim 14, wherein the plurality of interconnected open geometrically-shaped cells of the first geocell layer incorporates a drainage structure.
 17. The drainage base system of claim 14, wherein the plurality of interconnected open geometrically-shaped cells of the first geocell layer incorporates a network of drainage pipes.
 18. The drainage base system of claim 14, wherein a first selected ones of the plurality of open geometrically-shaped cells of at least one of the first geocell layer are filled with a first type of aggregate, and a second selected ones of the plurality of open geometrically-shaped cells of the first geocell layer are filled with a second type of aggregate.
 19. The drainage base system of claim 15, wherein a first selected ones of the plurality of open geometrically-shaped cells of at least one of the first and second geocell layers are filled with a first type of aggregate, and a second selected ones of the plurality of open geometrically-shaped cells of at least one of the first and second geocell layers are filled with a second type of aggregate. 